Multiple nation-states are investing in their capabilities to hack critical U.S. infrastructure, making defense of those networks a top priority, U.S. National Security Agency chief Admiral Mike Rogers said Thursday.

Attackers are seeking detailed information on how industrial control systems work, including obtaining engineering schematics and information on how such systems are configured, said Rogers, who spoke before the U.S. House of Representatives Permanent Select Committee on Intelligence.

Such information could allow hackers to shut down "very segmented, very tailored" parts of networks, such as turning off power turbines, Rogers said.

Industrial control systems are "big growth areas of vulnerability and action that we are going to see in the coming 12 months and it's among the things that concern me the most." Rogers said. "This will be truly destructive if someone decides that's what they want to do."

One or two nations besides China possess the capability to damage U.S. infrastructure, although Rogers said specific information on which countries is classified.

China and Russia are generally cited as nations with advanced cyberwarfare capabilities. The U.S. has stepped up its evaluation of critical infrastructure in the light of growing threats, focusing on 16 sectors as being critically important, including the power, aviation, financial and water industries.

There is a need for a set of rules to be applied to cyberspace, similar to laws governing warfare, Rogers said. Now, there is a "sense of risk" among nation states, groups and individuals that can easily acquire the ability to conduct cyberattacks, which could result in a loss of life.

"You can just do literally almost anything you want, and there isn't a price to pay for it," Rogers said.

The U.S. is seeing a trend in criminal groups, who have been motivated in the past by stealing information for profit, using some of the same attack tools used by nation-states, Rogers said.

The government believes that nation-states are trying to obscure their activity by using criminal gangs as surrogates to conduct cyberattacks. "That's a troubling development for us," he said.

He called for greater machine-to-machine sharing of information between private companies and the government in order to allow for a better defense.

Roger cautioned that the NSA, which has endured criticism for vast data collection programs revealed by its former contractor Edward Snowden, wants a public discussion on what kinds of data would be exchanged.